Peripheral primitive neuroectodermal tumor (pPNET), a rare, highly aggressive neoplasm of indetermined histogenesis, occurs typically in the soft tissues of the chest wall and the paraspinal region. Comprehensive diagnostic studies including histological, ultrastructural, immunohistochemical and molecular analyses have been stressed to diagnose this entity. We report a case of primary renal PNET which was incidentally found in a 59-year-old man who presented with generalized weakness for 4 months. He was diagnosed as a non-insulin dependent diabetes mellitus 15 years ago and has been made well by oral therapy. An ill-defined mass, measuring 3.5 3 cm, located in the left kidney and perirenal fat, was incidentally found by ultrasonogram during a renal diabetic examination. The mass was resected because of the unresponsiveness against one-year chemotherapy and radiation therapy. Grossly, a homogeneously solid, gray-white mass, measuring 2.8 1.8 cm, was noted in the mid portion of renal cortex. The mass showed severe adhesion to the perirenal fatty tissue. Microscopically, tumor cells were rather uniform, small round with scanty cytoplasm and often showed rosette formation. Ultrastructurally, they showed membrane-bound dense core granules, measuring 125~150 nm, intercellular junctions and microvillous cytoplasmic projections. The tumor cells were uniformly immunoreactive for neuron-specific enolase and were focally immunoreactive for CD99 (013), chromogranin, synaptophysin and cytokeratin. They were not reactive for S-100 protein, vimentin, Leu-7, leukocyte common antigen, desmin and smooth muscle actin. To our knowledge, this is the smallest renal PNET in literature.
Actins ; Adipose Tissue ; Antigens, CD45 ; Cytoplasm ; Desmin ; Diabetes Mellitus ; Drug Therapy ; Humans ; Intercellular Junctions ; Keratins ; Kidney* ; Middle Aged ; Muscle, Smooth ; Neuroectodermal Tumors, Primitive* ; Phosphopyruvate Hydratase ; Rosette Formation ; S100 Proteins ; Sarcoma, Ewing ; Synaptophysin ; Thoracic Wall ; Ultrasonography ; Vimentin

Extranodal natural killer (NK)/T-cell lymphoma, nasal type (NKTCL), is a malignant disorder of cytotoxic lymphocytes of NK or T cells. It is an aggressive neoplasm with a very poor prognosis. Although extranodal NKTCL reportedly has a strong association with Epstein-Barr virus, the molecular pathogenesis of NKTCL has been unexplored. The recent technological advancements in next-generation sequencing (NGS) have made DNA sequencing cost- and time-effective, with more reliable results. Using the Ion Proton Comprehensive Cancer Panel, we sequenced 409 cancer-related genes to identify somatic mutations in five NKTCL tissue samples. The sequencing analysis detected 25 mutations in 21 genes. Among them, KMT2D, a histone modification-related gene, was the most frequently mutated gene (four of the five cases). This result was consistent with recent NGS studies that have suggested KMT2D as a novel driver gene in NKTCL. Mutations were also found in ARID1A, a chromatin remodeling gene, and TP53, which also recurred in recent NGS studies. We also found mutations in 18 novel candidate genes, with molecular functions that were potentially implicated in cancer development. We suggest that these genes may result in multiple oncogenic events and may be used as potential bio-markers of NKTCL in the future.
Chromatin Assembly and Disassembly ; Herpesvirus 4, Human ; High-Throughput Nucleotide Sequencing ; Histones ; Lymphocytes ; Lymphoma* ; Prognosis ; Protons ; Sequence Analysis, DNA ; T-Lymphocytes

Immunoglobulin G4 (IgG4)-related kidney disease is a chronic immune-mediated fibro-inflammatory disorder characterized by multiple organ infiltration with IgG4-positive plasma cells, storiform fibrosis, and obliterative phlebitis or tumefactive lesions. Previous studies have explored IgG4-related kidney disease, increasing our understanding of its clinical manifestations, and pathological and radiologic findings. However, IgG4-related kidney disease can be misdiagnosed since it mimics malignancies. We report a case of a 77-year-old Korean man diagnosed with IgG4-related kidney disease with membranous proliferative glomerulonephritis, presenting with a renal pelvic mass suspected of being malignant.

Immunoglobulin G4 (IgG4)-related kidney disease is a chronic immune-mediated fibro-inflammatory disorder characterized by multiple organ infiltration with IgG4-positive plasma cells, storiform fibrosis, and obliterative phlebitis or tumefactive lesions. Previous studies have explored IgG4-related kidney disease, increasing our understanding of its clinical manifestations, and pathological and radiologic findings. However, IgG4-related kidney disease can be misdiagnosed since it mimics malignancies. We report a case of a 77-year-old Korean man diagnosed with IgG4-related kidney disease with membranous proliferative glomerulonephritis, presenting with a renal pelvic mass suspected of being malignant.

Macroglobulinemia is the result of an uncontrolled proliferation of lymphocytes and plasma cells in which a large IgM M protein is produced. IgM monoclonal gammopathy is recognized in a variety of lymphoproliferative diseases and Waldenstr?m's macroglobulinemia (WM) is the most frequent disease in this group. We report a case of nodal marginal zone B-cell lymphoma (Nodal MZBCL) accompanied by monoclonal macroglobulinemia. A 58-year-old man was admitted to the hospital with chronic fatigue and dyspnea. Physical examination revealed cervical, subaxillary, and inguinal lymphadenopathy. Histopathologically, monocytoid B cells with abundant pale cytoplasm and small nuclei infiltrated the cervical lymph node. The neoplastic cells were positive for CD 20, bcl-2, and IgM. The serum and urine electrophoresis showed monoclonal spike in the globulin region and immunoelectrophoresis demonstrated immunoglobulin of IgM, kappa type. Immunohistochemically, this monoclonal gammaglobulinemia (IgM, Kappa) was produced and secreted from the nodal MZBCL. This is the first report of nodal MZBCL accompanying macroglobulinemia in Korea.
B-Lymphocytes ; Cytoplasm ; Dyspnea ; Electrophoresis ; Fatigue ; Humans ; Immunoelectrophoresis ; Immunoglobulin M ; Immunoglobulins ; Korea ; Lymph Nodes ; Lymphatic Diseases ; Lymphocytes ; Lymphoma, B-Cell, Marginal Zone* ; Middle Aged ; Paraproteinemias ; Physical Examination ; Plasma Cells ; Waldenstrom Macroglobulinemia*

A metastatic melanoma to the gastrointestinal tract is observed in 1.5~4.4% of all melanoma patients. However, colonic and rectal involvement is less common. A 72-year-old woman was admitted due to abdominal pain and poor oral intake for 20 days. She had a 3 x 4 cm-sized mass on her right inguinal area 4 month ago, which was diagnosed as a malignant melanoma of the inguinal lymph node on excision biopsy. A large exophytic mass with an irregular ulcerlated, whitish patch, erythematous surface was observed in the hepatic flexure during colonoscopy. A histology diagnosis of a metastatic melanoma was made by an optical microscopy examination of the biopsies obtained during the colonscopy, and palliative right hemicolectomy was performed on account of a potential intestinal obstruction. We report a case of a metastatic melanoma of the colon with a review of the relevant literature.
Abdominal Pain ; Aged ; Biopsy ; Colon* ; Colonoscopy ; Diagnosis ; Female ; Gastrointestinal Tract ; Humans ; Intestinal Obstruction ; Lymph Nodes ; Melanoma* ; Microscopy